1. Field of the Invention
The present invention relates generally to a method for increasing the functionality of a media player/recorder device and, more particularly, to a method utilizing a title signal contained in digital video or audio data or encoded as a subsignal of a digital watermark signal contained in the digital video or audio data.
2. Prior Art
There is considerable interest in applying watermarking as a complimentary technology to encryption for copy protection of content on DVD video discs. It is currently proposed to insert 4-bits of copy control information. The first 2-bits indicate the copy permission associated with the content, i.e., free-to-copy, copy-once, copy-no-more and never-copy. The other 2-bits are used to control the associated analog copy protection system that prevents VHS recording of copy-no-more and copy-never material. The watermark is expected to code these 4-bits of information and 4 additional bits whose use is not yet defined.
In order for the copy protection system to work, all DVD recordersxe2x80x94preferably all (digital) video recordersxe2x80x94must have watermark detector circuitry that detects a watermark in the video and prevents the compliant DVD player or recorder from performing an illegal action, e.g., recording a copy-never movie. The cost of this detector may be small and is borne by the equipment manufacturers, despite the fact that there is no direct benefit to said manufacturers. In fact, adding copy generation control to DVD players and recorders not only costs manufacturers money but also reduces the functionality of the devices in the view of the consumer, i.e. consumers want to make copies of movies. Of course, both the equipment manufacturer and the consumer indirectly benefit, since without adequate copy protection technology, content owners would not publish their content on this media.
Nevertheless, consumers would like to copy pre-recorded content, and equipment manufacturers are therefore not inclined to install copy protection mechanisms in general and watermark detectors in particular. Thus, legislative and licensing mechanisms are being considered in order to compel the incorporation of copy protection schemes. While such measures are likely to be reasonably successful, it is nevertheless clear that equipment manufactures will only do the minimum necessary to meet their legal obligations.
Ideally, content owners would like to have a copy protection scheme that included increased functionality such that manufacturers and consumers would actually seek out such devices rather than non-compliant devices. Clearly, if a consumer is not permitted to make a copy of a movie, then some other functionality must be provided to compensate for this limitation.
Therefore it is an object of the present invention to provide a method in which a copy protection scheme adds increased functionality to a player and/or recorder device.
It is a further object of the present invention to provide a method in which a player and/or recorder device having a copy protection scheme is sought after by manufacturers and consumers of the device.
Accordingly, a method for utilizing a xe2x80x9ctitle signalxe2x80x9d contained in multiple copies of a title is proposed. Here, title refers to the title of a movie, for example xe2x80x9cWaterworldxe2x80x9d, and the multiple copies refer to say, each copy of the movie that is replicated onto a DVD disk or VHS tape. When a copy of a title is played, the title signal is compared with a player signal previously stored in a player device. Preferably, the data is digital image, video (both of which are hereinafter referred to as image data), or audio data. However, the proposed method is also applicable to analog recording and playback. The method comprises the steps of: providing data having the title signal; detecting, at the player device, the title signal in the data: comparing the title signal to the player signal stored at the player device; and performing an action based upon the comparison.
In a preferred implementation, the action is performed if the title signal matches the player signal, and the action is to notify the device user of the match and the winning of a prize. Other actions are also possible, including allowing the user to view hidden video chapters of the movie or hidden audio tracks. Any action that a user perceives as valuable is a candidate action.
In another preferred implementation, the title signal is a subsignal of a watermark signal encoded in the digital data, in which case the method further comprises the steps of: extracting the watermark signal from the digital data; and decoding the subsignal.
In yet another preferred implementation, the title signal is a subsignal of the copy control watermark signal encoded in the digital data, in which case the method further comprises the steps of: extracting the watermark signal from the digital data; and decoding the subsignal. The benefit of this arrangement is that while the copy control watermark may inhibit illegal recording and playback, it also provides added functionality that outweighs its perceived disadvantage. Consequently, users will actively desire compliant-devices. Of course, the method described need not be technologically coupled to the copy control watermark, but instead, might be coupled by licensing means.
In still another preferred implementation of the present invention, there is provided a method for increasing the functionality of a player device which displays digital image data or emits digital audio data having a watermark signal embedded therein. The method comprises the steps of: detecting, at the player device, the watermark signal in the data; extracting a title signal from the watermark signal; decoding the title signal; comparing the title signal to a player signal stored at the player device indicative of an attribute of the device, device user, data, or data owner; and informing the device user of the winning of a prize if the title signal matches the player signal.
Also provided are devices for carrying out the methods of the present invention.